More M157 issues :-( - S63L

[sambam2006]

Hi Guys,
Car: S63L W222 2016 (M157)
Has anyone heard this noise before? I only noticed this when I was showing off the noise of my car to a couple of friends.

When revving car makes a dump valve style noise, see video

Thing's I've already inspected:

• No errors in Xentry.
• Nothing out of the ordinary with belt or pulleys in engine bay, just had a quick visual look.
• No issues with driving, car accelerates normal and fast.
• No lights on the dash.

Any suggestions to where I can look?

Thanks

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[Petrol Pete]

Have you looked under the bonnet while the engine is being revved ? Belt tensioner 'flapping' ?? The noise appears as the rev's drop . ie: when the tension comes off the serpentine belt ??

Best of luck with whatever it is .

 

[sambam2006]

Have you looked under the bonnet while the engine is being revved ? Belt tensioner 'flapping' ?? The noise appears as the rev's drop . ie: when the tension comes off the serpentine belt ??

Best of luck with whatever it is .

I got a 2nd person to check but I couldn't replicate the same noise again. I will have to continue and monitor it